Edwakd h



EDWARD H. SHCROFT, OF. LYNN, MASSACHUSEJ'ITS.

Letters Patent No. 70,387, dated November 5, 1867.

IMPROVEMENT IN ELEVATORS.

alge Sagrada muret tain tlg'nte teitcpts gntent ma mating part nf ligt sume".

TO ALL WHOM YI'l MAY` CONCERN:

Be it "known that I, EDWARD H. ASHCROFT, of the city of Lynn, county of Essox,in the State of Massachusetts, have invented a new and improved Elevatorg and I do `hereby declare that the following isla fullA and exact description thereof, reference being had tothe accompanying drawing, making a part of-this speci- `icatiou, in which like parts are indicated by like letters in the several figures.

To cnableothers skilled in the art to make and use inyinvention, I will proceed to describe its construction and operation. In the drawingst I Figure 1 shows an elevation of my machine.

Figure 2, a central vertical section through the same; and

Figure 3, au cnd view. i

A represents the foundation or bottom ofi thc frame,'to which are secured uprights B and C, suitably braced attheir lower ends. D is a cross-piece, connecting the upriglits at their top, nTakihg altogether a strong, stable framework. '.lhcuprightC` is composed of two pieces, between which works a screw, E, the lowerend of which rests in a metal bed-plate, a. Above this, vand on the screw, is a bevel gear-wheel, If, and between this wheel and the bed-plate are'balls or friction-rollers, e. The bevcl-wheel 6 is secured to screw E, and it gears into another one, d, on a shaft, @,to which motion may-be given through a pulley, F, or in `any other obvious mechanical' way. G is a platform which rests upon a sleeve or female screw upon the screw E. The platform proper is supported `by a metallic braced frame, H. This at the top eneireles the screw E, and/at lits extreme outer end carries two frietionaoller's, gg, which beur upon the :frame-pieces c e. The horizontal arm of H'rests: upon the nut f, at the top of the latter. The other'enfl of H, that is, at z', works inei guide-sloth@ in upright B.

A-t thc lower end of H, where the diagonal arm meets the vertical one, I'also have two` friction-pulleys, It, bearing on the inside of frame'pieces C C, the same as do ur/ g on the outside. Y It isobvious what useful pur' poses these sets of friction-rollers serve. Thetop of the screw has a proper and secure guide'at the top of the frame. i

The operation is as follows: Motion being communicated to pulley F by another friction-pulley, or in' any other way, the shaft a is revolved, and with it the bevel-wheels eZ and e, and with the latter the screwE revolves, and, according to the direction inl lwhich it revolves, the sleeve or nut fruns up or down, carrying with .it the platform G. The nutf may be dispensed ,with by 1naking a screw in thc outer end of Il, where ity encireles the screw E. I prefer, however, the nut. It may also be attached to Il. l

Having thus described myinvention, what I claim as new, and desire to secure by Letters laent of the United States, i's- 'lhe combination of the frame Il, with its friction-rollers "L and y, and the screw E, construct-ed and .ope.- ating ifr the'manner'substantially as shown and described, and for the purpose set forth.

- u. u. ASHCROFT."

Witnesses: ,V

Josemi L. Oooains, J. W. Mrsrnrt. 

